The Tamron M118FM25 is an 25 mm, 1/1.8" format lens with a M25.5 x 0.5 filter size, -0.2% distortion, 120 resolution. The Tamron M118FM25 and the Tamron 1/1.8" M118 Lens family features C-mount for up to 9 mm image circle, 120 lp/mm, compact size, and close working distances.